CVE-2019-20844

mediumpriority · track · 26EPSS 0.004 · 37 %ileEUUS

grimoire priorityP3 · Track

Exploitable?

—

no known exploitation

Likely / severe?

0.43% (37th) EPSS

CVSS 4.3 · medium

Is it mine?

6 products

Check your exposure

Who says so?

3 sources

cnnvd · enisa_euvd · nvd

EPSS · scored 2026-10-27

An issue was discovered in Mattermost Server before 5.18.0, 5.17.2, 5.16.4, 5.15.4, and 5.9.7. An attacker can spoof a direct-message channel by changing the type of a channel.

cvss

Technical severity, 0–10. One row per scoring source.

6.5

010

base score 0–10 · higher = more severe · hover a vector to decode

v2.04.3mediumAV:N/AC:M/Au:N/C:N/I:P/A:Nprimary · NVD / NIST USexploitability 8.6 · impact 2.9

v3.16.5mediumCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:H/A:Nprimary · NVD / NIST USexploitability 2.8 · impact 3.6

v3.16mediumCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:H/A:N/E:Usecondary · CVSS-BT (t0sche)

weaknesses

The CWE weakness classes this flaw belongs to.

CWE-924USprimary

affected products (6)

Products and version ranges known to be affected.

n/a n/a≤ n/aenisa_euvdEU
mattermost mattermost server< 5.9.7nvdUScpe:2.3:a:mattermost:mattermost_server:*:*:*:*:*:*:*:*
mattermost mattermost server5.15.0 → 5.15.4nvdUScpe:2.3:a:mattermost:mattermost_server:*:*:*:*:*:*:*:*
mattermost mattermost server5.16.0 → 5.16.4nvdUScpe:2.3:a:mattermost:mattermost_server:*:*:*:*:*:*:*:*
mattermost mattermost server5.17.0 → 5.17.2nvdUScpe:2.3:a:mattermost:mattermost_server:*:*:*:*:*:*:*:*
mattermost mattermost server= 5.18.0nvdUScpe:2.3:a:mattermost:mattermost_server:*:*:*:*:*:*:*:*

also known as (3)

Other names and identifiers for this entity.

sources

Which sources assert this record, and when.

cnnvd enisa_euvd nvd NVD CVE.org MITRE

published 2020-06-19modified 2026-06-17

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+40 more

references (4)

External citations — patches, advisories, analysis.

scry

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